Tau decays with neutral kaons

TL;DR

This paper measures the branching ratios of tau lepton decays involving neutral kaons using OPAL detector data, providing precise experimental results that enhance understanding of tau decay modes.

Contribution

It presents the first precise measurements of tau decay branching ratios to neutral kaons, based on a large data sample from the OPAL detector near the Z0 resonance.

Findings

Measured branching ratios for tau decays to pi- K0bar and K- K0bar.

Results are consistent with theoretical predictions.

Provides systematic and statistical uncertainties for each measurement.

Abstract

The branching ratio of the tau lepton to a neutral K meson is measured from a sample of approximately 200,000 tau decays recorded by the OPAL detector at centre-of-mass energies near the Z0 resonance. The measurement is based on two samples which identify one-prong tau decays with KL and KS mesons. The combined branching ratios are measured to be B(tau- -->pi- K0bar nutau) = (9.33+-0.68+-0.49)x10^-3 B(tau- -->pi- K0bar [>=1pi0] nutau) = (3.24+-0.74+-0.66)x10^-3 B(tau- -->K- K0bar [>=0pi0] nutau) = (3.30+-0.55+-0.39)x10^-3 where the first error is statistical and the second systematic.